[CVE-2022-0396] Resolve #3112 TCP sockets stuck in CLOSE_WAIT

5818.	[security]	A synchronous call to closehandle_cb() caused
			isc__nm_process_sock_buffer() to be called recursively,
			which in turn left TCP connections hanging in the
			CLOSE_WAIT state blocking indefinitely when
			out-of-order processing was disabled. (CVE-2022-0396)
			[GL #3112]

Resolves: CVE-2022-0396

bind-9.16-CVE-2022-0396.patch

@@ -0,0 +1,81 @@
+From 33064cd077cf6fa386f0a5a840c2161868da7b3a Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Ond=C5=99ej=20Sur=C3=BD?= <ondrej@isc.org>
+Date: Tue, 8 Feb 2022 12:42:34 +0100
+Subject: [PATCH] Run .closehandle_cb asynchrounosly in nmhandle_detach_cb()
+
+When sock->closehandle_cb is set, we need to run nmhandle_detach_cb()
+asynchronously to ensure correct order of multiple packets processing in
+the isc__nm_process_sock_buffer().  When not run asynchronously, it
+would cause:
+
+  a) out-of-order processing of the return codes from processbuffer();
+
+  b) stack growth because the next TCP DNS message read callback will
+     be called from within the current TCP DNS message read callback.
+
+The sock->closehandle_cb is set to isc__nm_resume_processing() for TCP
+sockets which calls isc__nm_process_sock_buffer().  If the read callback
+(called from isc__nm_process_sock_buffer()->processbuffer()) doesn't
+attach to the nmhandle (f.e. because it wants to drop the processing or
+we send the response directly via uv_try_write()), the
+isc__nm_resume_processing() (via .closehandle_cb) would call
+isc__nm_process_sock_buffer() recursively.
+
+The below shortened code path shows how the stack can grow:
+
+ 1: ns__client_request(handle, ...);
+ 2: isc_nm_tcpdns_sequential(handle);
+ 3: ns_query_start(client, handle);
+ 4:   query_lookup(qctx);
+ 5:     query_send(qctcx->client);
+ 6:       isc__nmhandle_detach(&client->reqhandle);
+ 7:         nmhandle_detach_cb(&handle);
+ 8:           sock->closehandle_cb(sock); // isc__nm_resume_processing
+ 9:             isc__nm_process_sock_buffer(sock);
+10:               processbuffer(sock); // isc__nm_tcpdns_processbuffer
+11:                 isc_nmhandle_attach(req->handle, &handle);
+12:                 isc__nm_readcb(sock, req, ISC_R_SUCCESS);
+13:                   isc__nm_async_readcb(NULL, ...);
+14:                     uvreq->cb.recv(...); // ns__client_request
+
+Instead, if 'sock->closehandle_cb' is set, we need to run detach the
+handle asynchroniously in 'isc__nmhandle_detach', so that on line 8 in
+the code flow above does not start this recursion. This ensures the
+correct order when processing multiple packets in the function
+'isc__nm_process_sock_buffer()' and prevents the stack growth.
+
+When not run asynchronously, the out-of-order processing leaves the
+first TCP socket open until all requests on the stream have been
+processed.
+
+If the pipelining is disabled on the TCP via `keep-response-order`
+configuration option, named would keep the first socket in lingering
+CLOSE_WAIT state when the client sends an incomplete packet and then
+closes the connection from the client side.
+
+(cherry picked from commit afee2b5a7bc933a2d987907fc327a9f118fdbd17)
+---
+ lib/isc/netmgr/netmgr.c | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+diff --git a/lib/isc/netmgr/netmgr.c b/lib/isc/netmgr/netmgr.c
+index 3283eb6e4f..0ed3182fb6 100644
+--- a/lib/isc/netmgr/netmgr.c
++++ b/lib/isc/netmgr/netmgr.c
+@@ -1746,8 +1746,12 @@ isc__nmhandle_detach(isc_nmhandle_t **handlep FLARG) {
+ 	handle = *handlep;
+ 	*handlep = NULL;
+ 
++	/*
++	 * If the closehandle_cb is set, it needs to run asynchronously to
++	 * ensure correct ordering of the isc__nm_process_sock_buffer().
++	 */
+ 	sock = handle->sock;
+-	if (sock->tid == isc_nm_tid()) {
++	if (sock->tid == isc_nm_tid() && sock->closehandle_cb == NULL) {
+ 		nmhandle_detach_cb(&handle FLARG_PASS);
+ 	} else {
+ 		isc__netievent_detach_t *event =
+-- 
+2.34.1
+

bind.spec

@@ -51,7 +51,7 @@ Summary:  The Berkeley Internet Name Domain (BIND) DNS (Domain Name System) serv
 Name:     bind
 License:  MPLv2.0
 Version:  9.16.23
-Release:  1%{?dist}
+Release:  2%{?dist}
 Epoch:    32
 Url:      https://www.isc.org/downloads/bind/
 #
@@ -101,6 +101,8 @@ Patch157:bind-9.11-fips-tests.patch
 Patch164:bind-9.11-rh1666814.patch
 Patch170:bind-9.11-feature-test-named.patch
 Patch171:bind-9.11-tests-variants.patch
+# https://gitlab.isc.org/isc-projects/bind9/-/merge_requests/5987
+Patch172:bind-9.16-CVE-2022-0396.patch
 
 %{?systemd_ordering}
 Requires:       coreutils
@@ -401,6 +403,7 @@ in HTML and PDF format.
 %patch164 -p1 -b .rh1666814
 %patch170 -p1 -b .featuretest-named
 %patch171 -p1 -b .test-variant
+%patch172 -p1 -b .CVE-2022-0396
 
 %if %{with PKCS11}
 %patch135 -p1 -b .config-pkcs11
@@ -1123,6 +1126,10 @@ fi;
 %endif
 
 %changelog
+* Fri Mar 25 2022 Petr Menšík <pemensik@redhat.com> - 32:9.16.23-2
+- TCP connections with 'keep-response-order' are properly close in all cases
+  (CVE-2022-0396)
+
 * Fri Nov 19 2021 Petr Menšík <pemensik@redhat.com> - 32:9.16.23-1
 - Update to 9.16.23 (#2024210)